Apache and Mod_perl Glossary

Apache Application Program Interface (API) The Apache API lets you write programs in C that work directly through the server or even change the behavior of the server. This lets you do server-side programming that you could not do with the Common Gateway Interface (CGI). Apache Module An Apache module is a program that uses the Apache API to extend the capabilities of the Apache server. Mod_perl is a module. Perl programs that use the API through mod_perl are also Apache modules. They also happen to be written as Perl modules. Apache Server Root The directory under which Apache will look for its files. Many Apache configuration directives use directories that are relative to the Server Root. The default server root is defined at compile time, but a different server root can be given when starting the server. Dynamic Shared Object (DSO) An Apache module written in C must either be compiled directly into the server, or loaded dynamically at run time. Dynamically loaded modules are called DSOs. DSOs make it possible to add or remove modules at runtime without having to recompile the server. Mod_Perl Mod_perl uses the Apache API to embed a complete Perl interpreter inside Apache. This not only speeds up your CGI programs, but it makes almost all of the Apache API available to the Perl programmer! Perl Module A Perl module is a file that contains Perl packages. A Perl package is a special form of Perl program used to protect variable names and make reuse easier. Perl looks for its modules in a list of directories stored in the array @INC. Package Manager A program to make installing, verifying, removing, and upgrading programs easier. Files that are part of an application or group of applications are stored in a package file along with information about that package and what other packages it might require to run. When installed, this information is stored in a database where it can be queried later by the package manager. The two most popular package managers are the Red Hat Package Manager and the Debian Package Manager. RPM A package file used by the Red Hat Package Manager. Technically it is an RPM package.